Evidence of large recoil velocity from a black hole merger signal

velocity of Earth,” said Field. “Anything less than that, Earth’s gravitational pull will bring your keys back down to the ground. For a black hole to escape the gravitational pull of its host star cluster

This is the first observational evidence of a black hole moving fast enough it could theoretically be ejected from its host star cluster or galaxy, under the right circumstances."

Scott Field Associate Professor

or galaxy, you need even more velocity. This is the first observational evidence of a black hole moving fast enough it could theoretically be ejected from its host star cluster or galaxy, under the right circumstances.”

Given the kick velocity of GW200129, the team estimates that there is a less than 0.48% probability that the remnant black hole would be retained by globular (nuclear star) clusters after the merger.

The paper that applied these models to find this high-speed black hole is part of a larger ongoing study being led by two UMassD graduate students to reanalyze all gravitational wave observations seen to date with these new models. In this project, the GW200129 signal had interesting properties, which prompted a targeted study into what was going on with this event.

“We weren’t setting out to look for this. There were about 90 signals we were analyzing and this one led to a brandnew discovery,” said Field. “The project required state-of-the-art models of black hole mergers and gravitational waves, which were produced (with collaborators) as part of my NSF grants.”

The paper for the larger study is in preparation and will report on what Field teases as, “many more astrophysical surprises.”